Dimensions of Post Synaptic Density (PSD) at glutamatergic excitatory synapses

Range thickness ≈30nm: length ≈300nm enzymes
Organism Rat Rattus norvegicus
Reference Chen X, Vinade L, Leapman RD, et al. Mass of the postsynaptic density and enumeration of three key molecules. Proceedings of the National Academy of Sciences of the United States of America. 2005 102(32):11551-11556. doi:10.1073/pnas.0505359102 p.11551 left column 2nd paragraphPubMed ID16061821
Primary Source [2] Harris, K. M., Jensen, F. E. & Tsao, B. Three-dimensional structure of dendritic spines and synapses in rat hippocampus (CA1) at postnatal day 15 and adult ages: implications for the maturation of synaptic physiology and long-term potentiation. (1992) J. Neurosci. 12 , 2685-2705PubMed ID1613552
Method Abstract: "The total molecular mass of individual postsynaptic densities (PSDs) isolated from rat forebrain was measured by scanning transmission EM (electron microscopy)... Because the mass represents the sum of the molecular masses of all of the molecules comprising a PSD, it becomes possible to derive the number of copies of each protein, once its relative mass contribution is known."
Comments P.11551 left column 2nd paragraph: "The postsynaptic density (PSD) is a complex macromolecular signaling assembly anchored to the cytoplasmic side of the postsynaptic membrane (ref 1). The PSD, by conventional electron microscopy, is particularly prominent at glutamatergic excitatory synapses, appearing as a band of electron-dense material ≈30 nm thick and ≈300 nm long (primary source). The structure of the PSD is modified by synaptic activity (refs 3–5). These modifications are thought to underlie processes such as long-term potentiation (LTP) or long-term depression that, in turn, may underlie learning and memory (refs 1, 6, 7)."
Entered by Uri M
ID 114331